Starwatch: Venus, Mars, Jupiter and Saturn reveal the ecliptic

This week we can observe four of the five naked-eye planets (Venus, Mars, Jupiter and Saturn, but not Mercury) with the added bonus of a young moon, too. In doing so, we will be able to discern the ecliptic: the plane of the solar system, which defines the path in the sky that the sun, moon and planets all follow.

The chart shows a wide swathe of the sky, stretching from the south-east to south-west, as it will appear above London on 31 January at 6.45pm GMT. Starting at the western end of the panorama, a beautifully slender waxing crescent moon will be visible. Just 2.4 days old, only 6.2% of its visible surface will be illuminated.

Brilliant Venus continues to be unmistakable and has now entered Pisces, the fish. In between Venus and the moon, Saturn resides in Aquarius, the water bearer.

The next dot to connect is bright Jupiter. It will be found higher in the sky, in the constellation of Taurus, the bull. Finally, even higher and over in the south-east, situated in the constellation of Gemini, the twins, is the red beacon.

Joining these celestial objects with an imaginary line reveals the ecliptic path, which passes through the zodiacal constellations.